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Some five years ago, the consensus concerning this short and polemical book across several online literary venues was this: it's a good book of popular science and a bad book of philosophy.

This assessment is correct. This really is a pretty damn good of popular science. It succeeds brilliantly despite the heavy constraints that are imposed in any attempt to enable informing the current status of physical cosmology to the general public - as I shall explain in greater detail.

It also has barely nothing to contribute to the metaphysical issues behind concepts of nothingness. In that, the book is guilty of false advertisement - perhaps as part of an editor's ploy. It delivers neither the title nor the subtitle. What this book truly consists of is a dense expository history of over a century of physical cosmology in clear ordinary language.

The Intellectual Fraud Behind Popular Cosmology

The very motivation behind the literary industry of popular cosmology and theoretical physics is an unspoken socially acceptable intellectual fraud - albeit a relatively harmless one. It is an intellectual fraud in a way popular science books on many other scientific topics (such as evolutionary biology) are not. And that is because the type of knowledge that must be acquired to truly apprehend what is going on in theoretical physics and cosmology is knowledge of a tacit character that simply can not be acquired by reading books. This may even trick otherwise intelligent and educated persons into the false belief that they truly understand these advanced topics when in fact, they do not.

Let me assume that you, the reader, under reasonable standards, is a scientifically literate adult living in an urban and industrial society. Do you understand Natural Selection? More than likely you do. To put it in the bold words of philosopher Daniel Dennett, you can explain Natural Selection in a minute. Natural selection really is a simple idea - although one with tremendously complex consequences and, as an epistemic tradeoff, much prone to caricature.

But do you understand General Relativity? More than likely, you do not. And it doesn't matter how much Brian Greene and Stephen Hawking you've read and how many visually breathtaking documentaries filled with lively metaphors of basketballs deforming pillows you've seen and entertained in your imagination - and it doesn't really matter how wonderful you take your imagination to be. Not even ingenious uses of spandex will do.

To truly grasp General Relativity, one must master a myriad of mathematics and physics. This includes the much more accessible topic of Special Relativity. But it also includes the tools of tensor calculus and differential geometry (and just for this you'll generally require multivariable calculus and some solid understanding of linear algebra). Depth and differences in research traditions across physics will demand additional mathematics such as topology and analysis. This means that even if you are a person of above-average general intelligence, it will take years to master this content, in the form of undergraduate and most likely graduate-level courses in physics and mathematics.

Depending on the level of your intelligence (and moxie) this will probably mean that one can only develop the required geometrical and physical intuition to truly understand General Relativity through a mostly solitary mental journey of laborious homework, amidst pages of scribbled exercises and piles and piles of mistakes. It is much more cognitive demanding than grasping a simple algorithm such as Natural Selection. If you can do it, you'll be a part of a selected intellectual elite that has a special understanding of the cosmos.

If you lack this know how, you are not qualified to understand and much less to criticize General Relativity. It really is that simple. Tough luck for physics crackpots.

Think you understand String Theory? That is even more unlikely. For General Relativity just is one of the behemoths you need to master to understand these families of theories. The obsession of contemporary cosmology with n-dimensional manifolds starts with Kaluza-Klein Theory right after the development of General Relativity (for a popular historical overview, I recommend [1]). To understand String Theory, you need to be intimately acquainted with the formalisms of Lagrangian and Hamiltonian Classical Mechanics, the mysteries of Quantum Field Theory, some Group Theory and more.

And that's why popular cosmology is a fraud. Humans, in general, are superb storytellers but terrible mathematicians [2].

Succeeding in an Impossible Task

Given these hard facts, how should an intelligent and scientifically literate dilettante that is humble and intellectually honest behave? One can muster here a distinction between belief and acceptance ([3], Chapter 4). As a whole, the literature concerning this distinction states that while "belief" is an involuntary and irresistible act, "acceptance" is a willful deliberation or commitment. If the belief in counter-intuitive empirical statements is the consequence of deep understanding, i.e., the through and through acquisition of the tacit knowledge required to engage with the relevant alongside an honest evaluation of the evidence, then dilettantes with mere procedural knowledge of General Relativity cannot believe it. But they may accept it.

You are epistemically warranted to accept the conclusions of high-caliber cosmologists and theoretical physicists. Their authority is a proxy for the reasons and evidence over which their claims are justified. Let them do the thinking.

Good Science

Given this pessimistic panorama, I was pleasantly surprised with the output of Krauss. His prose is at least as good as the best popular cosmology I've read, from Victor Stenger and Michio Kaku. Krauss joins the ranks of talented popularizers of science that are also first-rate scientists.

Krauss is truly talented in this overbearing task of condensing material comprising a full century of understanding of physics.

As someone who has devoured a fair share of popular cosmology and theoretical physics since teenage years, this book still managed to deliver novelty in both concept and presentation. It displays a never-ending succession of instances of how our common sensical intuitions are broken down when we confront the structure of empty space. For instance, Krauss is an avowed realist on the existence of virtual particles; they truly are there and are not merely heuristic computational devices (for a classic alternative interpretation, see [4]). Here's one of the bolder sections:

“[C]onsider the [nonzero energy] electric field emanating from a charged object. It is definitely real. You can feel the static electric force on your hair or watch a balloon stick to a wall. However, the quantum theory of electromagnetism suggests that the static field is due to the emission, by the charged particles involved in producing the field, of virtual photons that have essentially zero total energy. These virtual particles, because they have zero energy, can propagate across the universe without disappearing, and the field due to the superposition of many of them is so real it can be felt.”

I have never seen a more striking display of the contrast between the concreteness of the everyday experience of our Umwelt and what we way find at scales very far away from our notional world.

“Here is a snapshot of how things actually look. It is not a real photograph of course, but rather an artistic rendering of the mathematics governing the dynamics of quarks and the fields that bind them. The odd shapes and different shadings reflect the strength of the fields interacting with one another and with the quarks inside the proton as virtual particles spontaneously pop in and out of existence.”

In the book you only see a slice of an existing animation; I found the entire thing through the wonderful blog Back Reaction by theoretical physicist Sabine Hossenfelder. This animation is known as the "Quantum Chromodynamics Lava Lamp", and it is the output of the research of theoretical physicist Derek B. Leinweber. Here it is:

This simulation displays the action density of the quark and gluon field fluctuations of "empty" space. It was featured in the lecture of the 2004 Nobel Prize of Physics.

“The proton is intermittently full of these virtual particles and, in fact, when we try to estimate how much they might contribute to the mass of the proton, we find that the quarks themselves provide very little of the total mass and that the fields created by these particles contribute most of the energy that goes into the proton’s rest energy and, hence, its rest mass. The same is true for the neutron, and since you are made of protons and neutrons, the same is true for you!”

Simply amazing - for the non-instrumentalist on virtual particles, at least.

Right on Philosophy

Of the many diatribes that Lawrence Krauss (and after him, other physicists such as Freeman Dyson) delivered against academic philosophy, one lesson is absolutely correct; most of what passes as "philosophy of science" is of little cognitive value.

One cannot do philosophy of science without understanding science. It is insane that there are philosophers of physics can't calculate a simple derivative. I've recently read Sir Anthony Kenny's History of Modern Philosophy and he makes the same exact point in his chapter delineating the development of physics from natural philosophy: "such a discipline [contemporary philosophy of physics] can only be pursued by those with more knowledge of the modern science of physics" ([5], p.180).

There are excellent philosophers of physics around who truly know what they are doing - researchers such as Bas Van Fraassen, Décio Krause, James Ladyman, Mario Bunge, Newton da Costa, Steven French and Otávio Bueno.

Philosophical folklore disguised as adamant historical tradition tells us that engraved at the door of Plato's Academy, it read "Let no one ignorant of geometry enter!". It's a good story, but it is probably false. Nevertheless, the spirit is absolutely right on; "Let no philosopher ignorant of science do philosophy of science!".

Bad Philosophy

I agree with the general sentiment; Krauss really adds nothing to the perennial problems of nothingness and ex nihilo existence as they have been formulated throughout most of the history of Western philosophy. For instance, he writes:

I suspect that, at the times of Plato and Aquinas, when they pondered why there was something rather than nothing, empty space with nothing in it was probably a good approximation of what they were thinking about.

I know very little about the metaphysics of Plato and Aquinas but I know enough to know their conceptions of "nothingness" are more abstract than empty space. Krauss' suspicion is false.

However... I do know a thing or two about my Greek intellectual great-great grandfathers, Leucippus and Democritus. Under their framework, Krauss' suspicion is spot on. For the early atomists, "Nothingness" (or Nonbeing) was identified with "The Void"; the ontological correspondent to "The Full" of Eleatic philosophy were the atoms. So here we have at least one veritable philosophical tradition that shares this conception of nothingness ([6], Chapter 6).

Something from Nothing?

But what would a reasonable addition to this philosophical problem look like? I hold that the epistemic space of solutions to philosophical problems falls into four cases; there are problems solvable through empirical methods, problems solvable through a priori methods (and if strong forms of empiricism are correct, this category gets subsumed by the later), there are pseudo-problems and there might be unsolvable mysteries and antinomies. Concerning this issue, my unrelenting scientism acquires a logical positivist flavor. It is my opinion that most problems stemming from issues of nothingness are pseudo-problems; they superficially look like answerable questions that mandate unique non-arbitrary answers but they are not. One of my favorite papers that explicitly follow this line of reasoning is Stephen Maitzen's "Stop Asking Why There's Anything" [7]. I submit that Maitzen's remarks may be generalized to surrounding questions involving things and non-things.